Thulite is a manganese-bearing variety of zoisite characterized by its distinct rose-pink to reddish-pink color. It typically occurs in massive or granular form within metamorphic rocks and is highly prized by lapidary collectors for carving and cabochons.

Hardness

6-6.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineraluncommonZoisite family

Thulite

Also: Unionite, Rose Zoisite

Hardness: 6-6.5
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this thulite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch thulite with a known reference. Thulite sits at Mohs 6-6.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: white.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous.
4
Match the color range
Compare against the expected color range: pink, reddish-pink, rose-red.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: massive, granular, rarely prismatic.

Often confused with

Thulite vs. its common look-alikes, and how to tell them apart in the field.

How to tell apart: Thulite is noticeably harder (Mohs 6-6.5 vs. 3.5-4).

Compare →

Often found alongside thulite

Minerals reported to co-occur with thulite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: Ca₂Al₃(SiO₄)₃(OH)
Mohs hardness: 6-6.5
Density: 3.1-3.4 g/cm³
Colors: PinkReddish-pinkRose-red
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Orthorhombic
Crystal habit: Massive, granular, rarely prismatic
Cleavage: Perfect
Rarity: Uncommon
Uses: Collector, Lapidary, Decorative
Host rock: metamorphic rocks, specifically hydrothermally altered limestone and skarns

Where rockhounds find thulite

8 mapped spots

Classic worldwide localities

Leksvik, Norway
Telemark, Norway
Otter Lake, Canada
San Bernardino County, USA
Aust-Agder, Norway

Field-hunting tip

Where it forms: metamorphic rocks, specifically hydrothermally altered limestone and skarns. If you start seeing calcite, quartz, tremolite in float, you are in the right ground. Typical habit: massive, granular, rarely prismatic. Train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Nevada, North Carolina, Georgia. Start trip planning there.

Browse 8 U.S. spots for thulite →

More thulite photos

Common questions

How do you identify thulite?+

Mohs hardness is 6-6.5. Luster: vitreous. The streak is white. Common colors include pink, reddish-pink, rose-red.

Where is thulite found?+

Notable localities include Leksvik, Norway; Telemark, Norway; Otter Lake, Canada; San Bernardino County, USA; Aust-Agder, Norway.

Can I find thulite in the United States?+

RockHoundR maps 8 thulite rockhounding spots across 6 U.S. states. The top states are Nevada, North Carolina, Georgia.

What rocks look like thulite?+

Thulite is most often confused with Rhodonite, Rhodochrosite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with thulite?+

Thulite commonly co-occurs with Calcite, Quartz, Tremolite, Diopside. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does thulite form in?+

Where it forms: metamorphic rocks, specifically hydrothermally altered limestone and skarns. Working float back to the host body is the standard way to chase a fresh occurrence.

What is thulite used for?+

Thulite is used in collector, lapidary, decorative.

Find thulite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.